I would like to see them make a Commando pro that temporarily disable turrets or in some other way help with clearing out player structures, because this was just straight up ridiculous.
Assassin: Cloak and smoke bomb. Turrets don't detect Cloak, Smoke bomb stuns them too.
Megabeth: Distanced Rocket shots, Disku. Rockets have no falloff damage, so just spam a clip from a distance. Disku stuns, and does solid damage.
Gunner: Secondary weapon bomb shots. Carpet bombing from range, does a good job of pestering anyone who panics, and tries to heal the turrets.
Combat Girl: Toss you own Kitty to distract the enemey turret, while blasting it with your nailgun. Her lazer can also take out an entire closely-knit enemey kitty nest easily.
Karl: Seconday weapon bombs do a great job, short out stops them, laser's alt fire also can help some.
Going juiced for no-falloff crits for destroying turrets also works wonders.
Normally, to set up these turret traps, the Support or Combat Girl is going to detach from their team, and go at it alone... perfect time to single them out and kill them. Sparks and Assassins make solo-turret setup a nightmare...